Third to richard wilson smith



N0. 6|6,066. Patented Dec. l3, I898. D. H. FERGUSON.

FIREPBDOF DOOR, SHUTTER, &c.

(Application fil d Oct. 23, 1897.)

(No Model.)

I il MW) WITNESSES JNVENTOR frymon/ INITED STATES PATENT Prion,

DAVID I-IISLOP FERGUSON, OF MONTREAL, CANADA, ASSIGNOR OF ONE- THIRD TO RICHARD \VILSON SMITH, OF SAME PLACE.

FIREPROQF DOOR, SHUTTER, 84,0.

SPECIFICATION forming part of Letters Patent N 0. 616,066, dated December 13, 1898.

Application filed October 23, 1897. Serial No. 656,176. (No model.)

( To aZZ whom it may concern.-

Be it known that 1, DAVID HIsLoP FERGU- sON, of the city of Montreal, in the district of Montreal and Province of Quebec, Canada, have invented certain new and useful Iniprovements in Fireproof Doors, Shutters, WVainscoting, or the Like; and I do hereby declare that the following is a full, clear, and

exact description of the same.

This invention relates to fireproof doors, shutters, wainscoting, and the like for buildings, and has for its object the providing of a comparatively inexpensive and light in weight, durable, and fireproof article without the use of metallic or other stiffening; andspecification, in which- Figure 1 is a face View, partly in section, of a door constructed according to my invention; Fig. 2, a transverse horizontal sectional view thereof, taken on line 2 2, Fig. 1; Fig. 3, a similar view to Fig. 1, but of a door of heavier design; and Fig. 4, a transverse horizontal sectional view thereof, taken on line at 4, Fig. 3.

Similar numerals refer to similar parts throughout all the views.

It is known that articles made from woodfiber or asbestos-fiber pulp, if the binding is of a hygroscopic nature and if it has to be used, (as in paper-making it must necessarily be so,) warps and twists from the effects of the different quantities of moisture carried by the air, the substance of the Wood-pulp and binding material of asbestos absorbing the moisture when the air is surcharged therewith and giving it off again when the air becomes dry, thus causing flat articles made from such materials to twist and warp to an inconvenient degree and in some cases debarring the use of them unless reinforced by metal supports. Wood-pulp for that reason has so far proved a failure, and asbestos, the fibers of which are scarcely at all influenced by moisture, warps or twists badly even when it has been attempted to decompose and set the binding.

In practice it is found that the pores of the article become filled with the binding material so completely that when immersed in the decomposing solution it decomposed on the surface, leaving the center or core unaffected and, when dried, subject to the Warping influence of moist and dry atmosphere, the moisture being gradually carried from the outside to the center, which increases in bulk unevenly and causes the objectionable warping.

On first immersing the article in the decomposing solution it is immediately drawn in by capillary attraction, and as it enters the solution attacks the outside layer first, the different elements rearranging themselves, the insoluble parts remaining in situ and the soluble parts being carried forward by the advancing solution, filling up and moistening the center and completely blocking the entrance of the virile solution, and though apparently set and decomposed itstill thus retains an undecomposed core, which is subject to a shrinking and swelling from a deprivation or supply of atmospheric moisture unless retained in the solution for months to allow of osmosic action or the slow interchange of particles, which is a matter involving long delay.

' We have an analogous case in the tanning of hides, which although no thicker than oneeighth or three-sixteenths of an .inch it takes months to form the required combination and leave the core or center of the hide converted into leather. To form a non-hygroscopic article and one which will not warp or twist, these difficulties must be faced and objections overcome.

In carrying out my invention I take asbestos fiber and pulp it as in paper-making, using non-combustible binding material, such as silicate of soda in a weak solution, so that in drying it will do little more than coat the surface of the fibers, but not strong enough to make a mucilaginous filling for the pores, and which when dry will leave the material porous and compact, but not very stiff or strong. The fiber so pulped I press in male and female molds or dies, which are provided with drainage to permit the surplus solution to escape. These dies or molds are formed to emboss one-half of side of a door, preferably, with stiles 5, rails 6, muntins 7, and panels 8. These molded halves are allowed to dry and are then provided with wood or metal sides four or five inches high, with a rubber edge to make a water-tight joint between them and the half-door. These sides, with the half-door, form an open box, which is filled with a solution of calcium chlorid, which is allowed to stand until the percolate comes through like a filter, thus insuring a thorough contact of the silicate of soda and the chlorid. The percolate at first comes through as salt and water; but as the decomposition goes on the percolate changes to calcium chlorid, showing that the settling is completed when the chlorid of calcium comes through. The liquid then remainingis poured off and the door allowed to stand awhile to drip. It is then again filled with a solution of silicate of soda a little stronger than the first and this is allowed to percolate through the door in a similar manner until'the solution begins to come through as silicate, when the box is again emptied of the silicate and recharged with calcium chlorid, and when that comes through as the percolate the chlorid is emptied and the box filled with pure water, which is allowed to percolate through the door to remove any uncombined silicate or soluble matter that may remain. At this stage the percolation becomes very sluggish, as the interstices are nearly filled, and the wateris allowed tov drain completely, and the half-door is then dried in a hot room. The action of the calcium chlorid on the silicate of soda is to break up the combinations of both and their component parts and form new combinations. The chlorid of calcium goes into combination with the sodium to form chlorid of soda or common salt, (soluble,) and the calcium goes to form with the silica silicate of calcium, (insoluble). The salt is washed out and leaves behind the fibers bound together by silicate of lime, which is actually a stone binding and perfectly non-hygroscopic, and when this is done and the halves or sides dried I cement or otherwise fasten them together.

The embossing makes the door perfectly stiff without the aid of metallic or other extraneous stiffening. Such a door is admirably suited for the inner doors of a suite of offices or such like; but for a door for, say, the entrance from a hall to the suite I prefer to provide edge strips 9 and studs 10 and secure them between (see Fig. 4) the two halves and fill the spaces thus formed with fiberized asbestos 12 or other incombustible material, while the necessary rigidity is imparted 'to those portions of the doors or shutters which carry the hinges and look by solid filling-pieces or extensions 11, preferably molded in one, with the halves of the door forming part of the edge strips and halves and occupying the inside space at the points where said hinges and lock are to be secured. This makes a strong stiff door, at once fireproof, light in weight, and impervious to heat, cold, or sound, and an article that will not twist or warp, while shutters, wainscoting, and the like may be made in the same manner, but with only one side embossed, and all may be finished by being veneered with wood or other material, as at 13, or painted or otherwise decorated, as may be desired.

Although I consider the foregoing to be the preferable manner of constructing articles of the class described according to my invention, yet, if desired, the door, wainscoting, and the like may be made as follows: A sheet of ordinary asbestos millboard may be used as the main board and hardened and rendered non-hygroscopic by first soaking in the binding material, after which it is carefully dried to prevent warping and subsequently soaked in the decomposing salt solution, while the stiles, rails, and muntins are also separately cut from ordinary asbestos millboard treated similarly to the main board and then attached to same on both sides. These additional pieces, while completing the resemblance to a paneled wood door, serve also to stiffen and reinforce the main board, so that this may be reasonably thin.

What I claim is as follows:

1. A fireproof door, shutter, wainscoting or the like formed of asbestos hardened and rendered non-hygroscopic.

2. A fireproof door, shutter, or the like of asbestos formed to imitate the pane1s, stiles, rails and muntins thereof hardened and reudered non-hygroscopic.

8. A fireproof door, shutter, wainscoting or the like, consisting of asbestos hardened by silicate of soda and rendered non-hygroscopic by calcium chlorid.

4. A fireproof door, shutter, wainscoting or the like, consisting of asbestos hardened by silicate of soda and rendered non-hygroscopic by calcium chlorid and provided with a veneer of wood.

5. A fireproof door, shutter, wainscoting or the like consisting of asbestos in two halves hardened and rendered non-hygroscopic, arranged with a space between them and secured together, and a filling of fiberized asbestos or other fireproof material, for said space.

6. A fireproof door, shutter, wainscoting or the like, consisting of asbestos pulp molded into shape to imitate the panels, stiles, rails,

and muntins, hardened by silicate of soda and rendered non-hygroscopic by calcium chlorid, for the purpose set forth.

In testimony whereof I afiix my signature in presence of two witnesses.

DAVID I-IISLOP FERGUSON.

Witnesses:

M. HOPPER, H. K. FERGUSON.

ISO

IIO

It is hereby certified that Letters Patent N 0. 616,066, granted December 13, 1898,

upon the application of David Hislop Ferguson, of Montreal, Canada, for an improvement in Fireproof Doors, Shutters,&c., were erroneously issued to said Ferguson,

and Richard Wilson Smith as assignee of one-third of the'said invention; whereas said Letters Patent should have been issued to said Ferguson and Richard Wilson Smith and Robert Thomas Hopper, said Smith and Hopper being owners of two-thirds interest, as shown 'by the record of assignments in this office and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed, countersigned, and sealed this 10th day of January, A. D., 1899. I

[SEAL] WEBSTER DAVIS,

Assistant Secretary of the Interior. Oountersigned C. H. DUELL,

Commissioner of Patents. 

